The invention relates to a method for assembling sets of documents wherein documents are successively fed and gathered into sets.
According to a method known from practice, the composition of sets of documents which have been fed separately is controlled by counting, during the formation of each set, the number of documents being fed and discharging gathered documents collectively when according to the count a specified number of documents have been gathered. This number should be set at the desired number of documents per set.
A drawback associated with this known method is that the risk of counting errors is substantial. Moreover, an error also affects the composition of subsequent sets, so that following an error the subsequent sets do not contain the correct documents either but contain one or more documents of a next or a preceding set. Counting errors may for instance arise when two documents are being fed simultaneously instead of consecutively. A further drawback of this known method is that the number of supplied documents that are to be discharged simultaneously as a set has to be set anew whenever a set consisting of a different number of documents than the preceding set is to be gathered. This means that this method does not enable efficient implementation of the composition of sets consisting of different numbers of documents in random order.
According to U.S. Pat. No. 3,260,517, for the composition of sets of documents, use is made of several feeding stations each loaded with a number of identical documents. For the composition of the sets, documents are fed by one or more of the feeding stations. For each set, different combinations of feeding stations can be selected for feeding documents. The selection of the feeding stations occurs in accordance with signals which have been read from a main document. These signals represent the set composition instructions for a set to be composed starting from the main document in question.
A drawback of this known method is that for each series of sets to be composed, it must be specified which documents are to be loaded into which feeding stations, and that these documents must then be loaded into the feeding stations prior to the preparation of that series of sets.
A further drawback is that if an error is made in drawing up the specification of the documents to be loaded into the feeding stations or in loading those documents, so that a feeding station is loaded with other documents than was envisaged in drawing up the main document, a different document than intended will be added to the main document upon activation of the feeding station in question.